Technical Field
The present invention has to do with a much needed improvement of the tools used in the field of commercial nuclear power plants. Nuclear reactors have a reactor core made up of a number vertically positioned and elongated fuel rod bundles that provide the necessary nuclear materials or elements to heat water circulating the fuel bundles. When the fuel rod bundles have been depleted their nuclear materials are termed “spent” and a re-fueling of the reactor core must be performed. In re-fueling or maintenance the “spent” bundles are removed from the reactor core, remaining still useable “unspent” bundles are repositioned to the center of the reactor core, and new fuel rod bundles are added to the radially outer dimensions of the reactor core. Each fuel bundle has a relatively confined cavity space into which it must fit as it exists alongside the other vertically positioned bundles. The positioning of the new fuel bundles and the re-positioning of the unspent bundles requires tools that provide a manual dexterity to the workers. The bundles must be positively connected on the bottom of the reactor and their correct attachment and alignment is a critical part of the re-fueling operation. Because the water level of the reactor core is not drained and the water is not cooled for the re-fueling operation, special tools are required for the removal, insertion and cleaning of the bundles and cavities of the reactor core. Very special tools already have been developed for the removal, insertion and placement of the fuel bundles, but in addition to those tools there are other tools that are necessary for performing maintenance while the bundles are removed and before they are replaced. Maintenance workers extend tools into the watery cavities in order to perform a variety of required tasks and these tools usually comprise elongate, segmented, hollow poles, referred to as masts. On the distal end of the masts are attached tools that may be of the gripping, wrenching, rotating, or brushing type, and if they are pneumatically operated, usually have their air supply hoses extend along the exterior length of the masts. When using such segmented masts it is very important that the masts do not become disconnected from one another when being twisted and turned by the workers and further that they do not introduce any foreign materials to the reactor core. In current practices the existing segmented masts may be joined by threaded connections or pinned arrangements and duct tape is commonly used over the jointed section to aid in holding the masts together or intact during use. Duct tape is certainly not strong enough and creates the possibility of introducing its own foreign material into the reactor core. Duct tape also does not positively prevent any broken pins, springs, or other material failures from contaminating the core. Foreign material in the core area is extremely undesirable.